Simple Choice retention offer: $10 x 6 months. Is that really the best they can do?

10+ years T-Mobile customer here still on a grandfathered Simple Choice plan with 7 lines, 2.5GB data each. Chatted with support last night about loyalty/retention options since the bill keeps creeping up. They gave me $10/month for 6 months and said that's the highest loyalty offer available on my account, and I can ask again after the 6 months are up. Is that really the ceiling? Curious whether anyone on Simple Choice (or other grandfathered plans) has gotten better retention offers lately. I'm aware of the trade-in offers going around, but I'm wary. I had a bad experience in the past where promised monthly bill credits didn't apply correctly and it was a whole saga to get it fixed. Any recent datapoints on trade-in promos actually working smoothly, or is it still a headache to make sure the credits show up every month? Not looking to switch plans but may change service providers